Return-path: Received: from mail-ie0-f173.google.com ([209.85.223.173]:36743 "EHLO mail-ie0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751149AbbBDL50 (ORCPT ); Wed, 4 Feb 2015 06:57:26 -0500 Message-ID: <1423051045.907.108.camel@edumazet-glaptop2.roam.corp.google.com> (sfid-20150204_125731_338082_C854D4A2) Subject: Re: Throughput regression with `tcp: refine TSO autosizing` From: Eric Dumazet To: Michal Kazior Cc: linux-wireless , Network Development , eyalpe@dev.mellanox.co.il Date: Wed, 04 Feb 2015 03:57:25 -0800 In-Reply-To: References: <1422537297.21689.15.camel@edumazet-glaptop2.roam.corp.google.com> <1422628835.21689.95.camel@edumazet-glaptop2.roam.corp.google.com> <1422903136.21689.114.camel@edumazet-glaptop2.roam.corp.google.com> <1422926330.21689.138.camel@edumazet-glaptop2.roam.corp.google.com> <1422973660.907.10.camel@edumazet-glaptop2.roam.corp.google.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2015-02-04 at 12:35 +0100, Michal Kazior wrote: > > (Or maybe wifi drivers should start to use skb->xmit_more as a signal to end aggregation) > > This could work if your firmware/device supports this kind of thing. > To my understanding ath10k firmware doesn't. This is a pure software signal. You do not need firmware support. Idea is the following : Your driver gets a train of messages, coming from upper layers (TCP, IP, qdisc) It can know that a packet is not the last one, by looking at skb->xmit_more. Basically, aggregation logic could use this signal as a very clear indicator you got the end of a train -> force the xmit right now. To disable gso you would have to use : ethtool -K wlan1 gso off